In a known information processing system (also referred to as a multi-tier system), a process is distributed in a tier fashion among a plurality of computers. A three-tier system as a multi-tier system is known which includes a web server providing a interface for system use, an application (APP) server executing a process on the system, and a database (DB) server managing data. Each server executes a process in response to a process request from a user, and thus responds to the process request. With each computer performing a distributed portion of the process, reliability and response characteristics of the system are increased.
The information processing system performs a stable operation through an operation management. The multi-tier system is typically used in an important transaction system. High performance response characteristics are typically desirable in the process of the system. If the response characteristics of the system are degraded, it is desirable to learn a tier correctly at which a cause for a process delay occurs.
To identify a delay location over a computer, a specific agent may be performed on the computer, and a usage status of a hardware resource and a software resource may be acquired. In one available technique, a main cause of delay at any resource on the computer is analyzed based on the usage status.
In the multi-tier system, a usage status of a resource and an extension rate of a process time in a computer as a management target may be acquired based on acquired information of the computer. For example, in one available technique, a lack of resources and an extension of the process time help determine a tier of the computer suffering from a process delay.
In one contemplated method, a delay location in a multi-tier system is determined by estimating a process time and a response time in a computer responsive to a process request in accordance with a communication packet flowing over a network.
It is important to identify a tier (hereinafter also referred to as a computer) serving as a bottleneck as a process delay in the multi-tier system. If process delays take place at a plurality of tiers, a delay of a tier as a bottleneck may adversely affect a process of another tier. In such a case, the identification of the tier serving as the bottleneck and the removal of the cause for the bottleneck are efficient in view of increasing performance of the entire system.
The usage status and the process time of each computer may be acquired. If a known technique is applied to analyze the acquired data, a bottleneck may not be appropriately detected. For example, the number of processes executable in parallel may be limited by the setting of an application software program. In such a case, the computer may be free from the lack of resources and the process delay. With any of these techniques of related art, the computer has a difficult in detecting the bottleneck as an anomaly. The cause for the bottleneck may be overlooked.